Tuning



p 1933. F. ULRICH ET AL TUNING INVENTOR FRITZ ULRlCH FRANZ SAAB BY M2 ATTRNEY Patented Sept. 12, 1933 TUNING Fritz Ulrich, Berlin-Siemensstadt, and Franz Saar, Berlin-Neukolln, Germany, assignors to Siemens & Halske, Aktiengesellschaft, Siemensstadt, near Berlin, Germany, a corporation of Germany Application June 21, 1932, Serial No. 618,482, and in Germany June 30, 1931 4 Claims. (Cl. 116124.1)

The present invention is concerned with dial devices, especially for broadcast receiver. sets, in which a transparent dial or scale is used.

It is known in the prior art that dial devices in receiver sets may be designed in this way that the scale itself is made from some transparent material. In the rear of the dial moves an index hand of which a shadow or image is thrown upon the transparent dial. Illumination in this arrangement is produced in this manner that upon the index or pointer a small electric glow-lamp is secured. Arrangements of this kind, however, involve the drawback that only part of the dial is actually illuminated, while the rest thereof remains dark.

According to the invention, illumination of the dial in a broadcast receiver set comprising a transparent and illuminated dial is effected indirectly.

Figs. 1 and 2 by way of example illustrate an embodiment of the invention, Fig. 1 being a front elevation and Fig. 2 a side elevation. In both illustrations similar parts are designated by identical reference symbols. In the front panel 1 is fitted the transparent dial 2 in the rear of which moves a pointer 3 which is associated with the tuning means. Posteriorly of the scale is a semi-circular reflector 4 whose inner surface 5 is coated, for instance, with a dull-white paint. Secured upon a holder 6 is a glow lampfl which throws its light upon the inner face 5 of the reflector 4 so that the said inner face produces diffuse illumination of the scale 2, the pointer 3 being visible upon the scale 2 in the form of a dark spot or line.

For the purpose of facilitating the replacing of the glow-lamp 7 the holder 6 thereof is pivotally supported at 8. At right angles to 6 is disposed a piece of metal or the like 9, which may be secured upon the base-plate of the set, for instance, by means of a screw 10. Unscrewing screw 10, the lamp 7 conjointly with its holder 6 can be readily moved downwardly for replacement of the bulb. This position is shown by bold lines in Fig. 1.

While we have indicated and described a system for carrying our invention into effect, it will be apparent to one skilled in the art that our invention is by no means limited to the particular construction shown and described, but that many modifications may be made without departing from the scope of our invention as set forth in the appended claims.

What we claim is:

. 1. A radio tuning indicating mechanism of the type including an operating panel provided with a completely exposed translucent dial, a pointer positioned behind said dial, and a tuning means arranged to move said pointer across the entire rear face of said dial, having in combination therewith an illumination means, positioned behind said panel, for producing a shadow image of said pointer on said scale, a support, positioned behind said panel, for said illumination means, and additional means for moving said support and illumination means into a position where the latter may be replaced.

2. A radio tuning indicating mechanism of the type including an operating panel provided with a completely exposed translucent dial, a pointer positioned behind said dial, and a tuning means arranged to move said pointer across the entire rear face of said dial, having in combination therewith an illumination means, positioned behind said panel, for producing a shadow image of said pointer on said scale, a reflector surrounding said dial and pointer, a support, positioned behind said panel, for said illumination means, and additional means for moving said support and illumination means into a position where the latter may be replaced.

3. A radio tuning indicating mechanism of the type including an operating panel provided with a completely exposed translucent dial, a pointer positioned behind said dial, and a tuning means arranged to move said pointer across the entire rear face of said dial, having in combination therewith an illumination means, positioned behind said panel, for producing a shadow image of said pointer on said scale, a support, pivot ably positioned behind said panel, for said illumination means, and additional means for moving said support and illumination means into a position where the latter may be replaced.

4. A radio tuning indicating mechanism of the type including an operating panel provided with a completely exposed translucent dial, a pointer positioned behind said dial, and a tuning means arranged to move said pointer across the entire rear face of said dial, having in combination therewith an illumination means, positioned behind said panel, for producing a shadow image of said pointer on said scale, a support, positioned behind said panel, for said illumination means, and additional means for moving said support and illumination means into an exposed position where the latter may be replaced, and means for normally maintaining the moving means secured to said panel.

FRITZ ULRICH. FRANZ SAAR. 

